Synonyms for Modal (same or very similar meaning)
WordNet sense 1 (an auxiliary verb (such as `can' or `will') that is used to express modality):
modal auxiliary verb, modal auxiliary
WordNet sense 2 (relating to or constituting the most frequent value in a distribution):
average
WordNet sense 3 (conforming with or constituting a norm or standard or level or type or social norm; not abnormal):
normal
From the ODE community, based on WordNet
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